The present invention is related generally to the field of water purification and more specifically to a water purification device that can be inserted into a canteen that was filled from an impure water source and immediately allows the user to consume clean water directly from the canteen, without the need of a pump.
Campers, survivalists and military personnel all understand the importance of maintaining, or having access to, sufficient quantities of water when they are out in the wilderness and away from traditional clean water sources. The average human being, when stranded outside in the elements, cannot survive much longer than three days without water to drink. Unfortunately, water is one of the heaviest commodities that backpackers and military personnel must carry with them if they don't have access to a clean water source. This undeniable need for clean water coupled with the relatively unmanageable weight of water makes the ability to purify water out “in the field” quite desirable.
When it comes to the military, purification of water “in the field” is a problem with which they are still struggling. For purifying large quantities of water a large and loud piece of electrical machinery known as a “ROWPU” (pronounced Row-Poo) Reverse Osmosis Purifying Unit, is used. One ROWPU can easily provide a company size unit or larger with all the water it required as long as there was a water source from which to draw. Unfortunately, this easy to use piece of machinery cannot be used in a tactical setting. The ROWPU requires an electrical energy source, thus requiring a gas powered generator as an accompanying piece of machinery. Clearly the bulk and weight of this machinery is already prohibitive for the smaller infantry units. Other intolerable characteristics of the ROWPU include the noise that is made while operating. In a tactical setting, letting a generator run would be like giving a map of exactly where you are to the enemy. Something all good leaders try to avoid. Another drawback of the ROWPU and of all large-scale water purification devices is that all of the troops have to come to one spot to get the clean water. Gathering all of the troops in one place or even allowing the troops to be counted while passing by an observer is another one of those things that good leaders try to avoid.
In order to avoid the above undesirable characteristics of large-scale water purification devices, the military implemented the use of Iodine tablets. This allowed water purification abilities to be distributed down to the individual soldier. While this did cure the larger scale purification problems, it created an entirely new list of “tablet” (Iodine or Chor-floc) problems. To begin with, treated water has poor palatability. Existing iodine tablets leave a residual disinfectant when used to disinfect an individual's field water supply. As a result, the water has a very strong iodine taste that makes it unpalatable to the soldier. Additionally, iodine tablets do not reduce turbidity in raw water supplies, which reduces the soldier's desire to drink water and thus risk possible dehydration. A further “tablet” drawback is their lengthy disinfection time. Iodine tablets and Chlor-floc require at least 30 minutes of disinfectant contact time to inactivate bacteria and viruses. Finally, since no filtration is provided when using tablets there is inadequate disinfection of protozoan cysts. Most protozoan cysts cannot be inactivated using iodine tablets or Chlor-floc. These organisms must be physically removed from raw water. Failure to do this could result in sickness due to waterborne diseases such as Crytosporidiosis and Giardiasis.
What is needed is a water purification device that has the advantages of both the large scale (ROWPU) and distributed (tablets) water purification devices and none of the drawbacks of either of the methods. The ideal purification device would be small enough to be distributed to the individual soldier. It would reduce turbidity, remove protozoan cysts and not make noise. And perhaps most importantly, it would provide palatable water to the troops without the undesirable “iodine” taste. The present invention is directed at providing a water purification device that meets all of these requirements. In operation, the present purification device will not require all of the troops to gather or pass by one location in order to get clean water. The device can easily be issued to each soldier at the same time their canteens are issued. The device also provides filtration that reduces turbidity and removes causes of waterborne diseases from raw water. This filtration is provided without a pump. Finally, because of the unique multistage purifying apparatus in the present purifying device, clean water is provided to the soldier without an undesirable iodine taste.